The extra single quotes are escape characters.

“额外” 的那个单引号是换码符。

youdao

SolidDB strings are delimited by single quotes.

soliddb字符串使用单引号分隔。

youdao

The use of the two single quotes is discussed in the next section.

下一节讨论为什么要使用两个单引号。

youdao

So if I want to use a string as we'll call it which is a word or phrase generally, they always go between double quotes, David hence the quotes around David, and they are double quotes not single quotes intentionally.

当我们要表示单词啊，词组啊，句子啊等等这样的东西时,就会用到字符串，它们位于双引号之间，也就是这里双引号之间的，是双引号，不是单引号哦。

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Doll also quotes one random, unnamed single guy that believes if women were more withholding, guys would be more likely to commit.

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"I don't think there is a single child untouched by this war, " the report quotes a child called Safa as saying.

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